Microsoft opened its Windows 10 Technical Preview for Phones on Thursday by supporting just midrange to lower-end devices, could be annoying if you're using a phone like the Lumia 930 to test websites and apps.

Currently, just six phones can download the Windows 10 Technical Preview: the Lumia 630, 635, 636, 638, 730, and Lumia 830. Aside from the Lumia 830, Microsoft's "affordable flagship," the remainder are midrange Windows Phones that were released according to Microsoft's principle of driving Windows Phone market share by expanding its user base.

"We are starting with a limited set of devices supported for this first preview," Gabe Aul, the engineering general manager at Microsoft who has been the point man for Windows 10, said in a blog post. "Windows 10 will drive innovation across screens of all sizes and we will have new hardware from Microsoft and our partners, including new flagship phones."

Aul did say in a series of followup tweets that Microsoft's flagship phones--he specifically mentioned the Lumia 1020 and the 1520 by name--will be supported, just in subsequent releases.

Here's how to get the Windows 10 for phones preview

If you do own one of the supported phones, you'll need to do several things:

First, be confident that you want to run the technical preview of Windows 10 for phones on your phone. Unlike with a PC, you can't run a new phone OS inside a virtual machine.

"We haven't bricked a single phone during all of our internal testing, but it is NOT IMPOSSIBLE, so you should be aware that there is some potential risk for you," Aul said. "In addition, bugs could prevent access to important features for you, including phone dialing and other core functionality."

You'l also need to make sure your phone can recover from the Technical Preview in case something goes wrong. Microsoft said it's created a Windows Phone Recovery Tool in case something goes wrong, and you'll be able to "back out" of the process and go back to your standard Windows Phone build.

Next, join the Windows Insider Program, if you haven't already, and download the Windows Insider app from the Windows Phone store. You'll then need either to run the app or let the app push new builds to you.

Highlighted features in Windows 10 for phones

Aul and his boss, Joe Belfiore, the vice president in charge of the Operating System Group at Microsoft, highlighted a few of the features that the technical preview includes:

A full-size background image

More "quick actions," notifications that you can interact with and swipe away

Better speech-to-text functionality

The Photos app that Microsoft previously showed off at its Windows 10 event in Redmond.

The expanded quick actions place a number of options at your fingertips, including the ability to turn off and on VPNs, and the like:

With the improved "toast" notifications, you can just pull down the notification at the top and reply to a text, like so:

What's next? The integrated Office apps, for one. Microsoft has managed to shrink the entire Office ribbon user interface for small screens, making features like Track Changes available on smartphones. "In upcoming builds we'll also include the new Mail and Calendar Universal Apps from the Outlook team in Office, as well as IP-based messaging from Skype and others, integrated directly into Messaging experience," Aul added.

Bugs and downgrades

Microsoft also said that it had to downgrade or limit some features, including Cortana, which in the Windows 10 Technical Preview for phone is just a US-only, English-only feature.

The new release also has a hefty share of bugs, which include VPN functionality not working, alarms failing to migrate, cellular data failing to work while roaming, and syncing problems with the Microsoft Band. In most cases Microsoft said that it has found workarounds; check the blog post for hotfixes.

Disappointed fans

While the new preview excited fans on Twitter, many were disappointed they couldn't try it out. Still, it appears that most Windows Phone users will have a chance to play with the technical preview of Windows 10 for phones at some point in its lifecycle.

"The majority of Lumia phones, from our most advanced to the most affordable, can be upgraded to Windows 10," Aul wrote. Chances are, though, that you'll just have to wait.